Robinson testified that he acted in self-defense after more than a decade of disputes with Trask, his brothers and other family members. The disputes were over the Trasks hunting with dogs on Robinson’s land and the Trasks leaving an access gate unlocked.

The defendant told the jury that he thought the cellphone holder on Trask’s belt was a holster with a gun in it and he feared Trask would shoot him. Robinson also testified that he took the 15-pound crowbar away from the older man before striking him in the ribs and jaw. The final blow to Trask’s face was delivered once he was on the ground, according to testimony during the trial.

“It is hard to imagine a manslaughter that could potentially be more violent and heinous or that is more deserving of a sentence near 30 years,” Assistant Attorney General Andrew Benson, who prosecuted the case, said in his sentencing memorandum. “This kind of conduct is simply one step away from the utter disregard for the value of human life accompanying a depraved indifference murder, and it is certainly an extremely serious basic sentence.”

Benson recommended Robinson be sentenced to 30 years in prison with all but 10 years suspended and four years of probation. The prosecutor said there were no mitigating factors in the case.

An aggravating factor Benson cited is Robinson’s criminal record, which includes convictions for criminal trespass, drunken driving, operating after suspension and other misdemeanors. The last conviction was in 1989. Other aggravating factors Benson listed includes the effect of Trask’s death on his family and Robinson’s apparent lack of remorse.

Defense attorney Thomas Hallett of Portland wrote in his sentencing memorandum that a sentence of 10 years with all but three suspended and four years of probation would be appropriate.

“In this case, we have a law-abiding citizen thrust into an ongoing psychological battle with a powerful family of dog hunters,” Hallett said. “The use of his private property as he desired was pitted against the desire of dog hunters to be able to travel unimpeded in their search for game. Five to ten seconds changed everyone’s lives forever. A long prison sentence will serve no purpose.”

Robinson, who was free on bail before and during the trial, has been held at the Penobscot County jail while awaiting sentencing.